Are poisonous jellyfish still off the Jersey Shore?

Box Jellyfish off Point Pleasant last October (Weather Channel/Barnegat Bay News)

With Memorial Day weekend fast approaching, The Weather Channel is warning about this specific breed of jellyfish. National Geographic says Box Jellyfish produce a venom considered to be “among the most deadly in the world."

The jellyfish was spotted off the coast of Point Pleasant last October, according to Point Pleasant First Aid and Emergency Squad Captain Jerry Meany. Meany posted video of them on the Barnegat Bay Island, NJ Facebook page, but they have not been seen since. "Being tropical they can't survive in our Jersey water temps," explains Meany. "They seemed to die off when the water chilled." He says we won't know until June if they will return.

"I saw it come up, it surfaced, broke the water a little bit and then went down again and kept swimming to the same spot over and over again," Meany told the Weather Channel. He saw a second one off Bay Head a week or two later. There were six sightingsof the Box Jellyfish last season along Ocean County beaches last year, including one in the Manasquan River.

Jack Gaynor, a Montclair State biology professor tested a sample and confirmed that Meany's find was a Box Jellyfish, which is normally found in the tropical waters of Australia. "What it was doing off the coast of New Jersey in October is a big mystery," says Gaynor.

Meteorologist Dan Zarrow says this summer's ocean temperatures are already 3-6 degrees above normal this year which could make for a more active jellyfish season. However, It's not clear if the boxy looking creatures, which are pale blue and transparent in color with as many as 15 tentacles coming off their body, have reappeared since last fall.

The Box Jellyfish's sting, according to National Geographic, can produce a toxin that is so "overpoweringly painful" that human victims "have been known to go into shock and drown or die of heart failure before even reaching shore. Survivors can experience considerable pain for weeks and often have significant scarring where the tentacles made contact."

Meany says his emergency squad is prepared if anyone gets stung this weekend.